On Fri, Feb 26, 2021 at 08:20:29AM +0800, Shiyang Ruan wrote:
> error = iomap_zero_range(VFS_I(ip), offset, len, NULL,
> - &xfs_buffered_write_iomap_ops);
> + IS_DAX(VFS_I(ip)) ?
> + &xfs_dax_write_iomap_ops : &xfs_buffered_write_iomap_ops);
Please add a xfs_zero_range helper that picks the right iomap_ops
instead of open coding this in a few places.
> +static int
> +xfs_dax_write_iomap_end(
> + struct inode *inode,
> + loff_t pos,
> + loff_t length,
> + ssize_t written,
> + unsigned int flags,
> + struct iomap *iomap)
> +{
> + int error = 0;
> + xfs_inode_t *ip = XFS_I(inode);
> +
> + if (pos + written > i_size_read(inode)) {
> + i_size_write(inode, pos + written);
> + error = xfs_setfilesize(ip, pos, written);
> + }
> + if (xfs_is_cow_inode(ip))
> + error = xfs_reflink_end_cow(ip, pos, written);
> +
> + return error;
What is the advantage of the ioemap_end handler here? It adds another
indirect funtion call to the fast path, so if we can avoid it, I'd
rather do that.
Also, shouldn't we cancel the COW rather than finishing it when setting
the file size fails?
